Cisco ASR 900 Series User Manual

•
Flex LSP is supported with the IPv4 template.
•
The ip rsvp signalling hello command is not mandatory and it can cause a large punt during the cutover
and can lead to unexpected results like BFD flapping.
•
VPLS over Flex-LSP is not supported.
•
Both IGP and FRR must be configured as clients for single-hop BFD when the WRAP protection is
enabled; only FRR cannot be the only client configured at midpoint.
•
Layer 3 VPN over Flex-LSP is not supported.
Restrictions for Non Co-routed Inter-Area Flex LSP Tunnels
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The dynamic path option feature for TE tunnels (tunnel mpls traffic-eng path-option number dynamic)
is not supported for inter-area tunnels. An explicit path identifying the area border routers (ABRs) is
required.
•
The MPLS TE AutoRoute feature (tunnel mpls traffic-eng autoroute announce) is not supported for
inter-area tunnels.
•
Tunnel affinity (tunnel mpls traffic-eng affinity) is not supported for inter-area tunnels.
•
Tunnel metric (tunnel mpls traffic-eng path-selection metric) is not supported for inter-area tunnels.
•
The re-optimization of tunnel paths is not supported for inter-area tunnels.
How to Configure Co-routed Flex LSPs
A co-routed bidirectional packet LSP is a combination of two LSPs (one in the forward direction and the other
in reverse direction) sharing the same path between a pair of ingress and egress nodes. It is established using
the extensions to RSVP-TE. This type of LSP can be used to carry any of the standard types of MPLS-based
traffic, including Layer 2 VPNs and Layer 2 circuits. You can configure a single BFD session for the
bidirectional LSP (that is, you do not need to configure a BFD session for each LSP in each direction). You
can also configure a single standby bidirectional LSP to provide a backup for the primary bidirectional LSP.
The configuration includes the following steps:
1
Enable basic MPLS Traffic Engineering on hostname PE1.
2
Map L2VPN pseudowire to a specific FLEX LSP tunnel.
3
Configure Flex LSP.
4
Enable BFD.
5
Enable Wrap and Fault OAM.
6
Enable BDIs on a core-facing interface.
MPLS Basic Configuration Guide, Cisco IOS XE Everest 16.5.1 (Cisco ASR 900 Series)
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Flex LSP Overview
Restrictions for Non Co-routed Inter-Area Flex LSP Tunnels

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English